I never played KOTOR, so I can't compare the two, but this game reminded me a lot of a few other games:

Flashback: Quest for Identity - Especially the missions in the Citadel reminded me of the middle sections of Flashback set in the New Washington area.

Xenosaga - I realize there were no little girls or giant robots in ME, but the overall environments, atmosphere and story reminded me a lot of Xenosaga.

Star Trek: The Kobayashi Alternative - This was an old text adventure set in a virtual version of the first Star Trek series where you could wander around the the Enterprise and navigate to any planet you knew the name or coordinates of and could have discussions with various aliens and crew using a limited standardized protocol.

It reminded me of Bioshock a bit...with all the morality things. Of course ME was more robust in that way but it sort of reminded me of it

Mass Effect reminded me of Anarchy online for some reason.

Mass Effect was most like Kotor. How you get to choose where your ship takes you. Mass Effect is basically a non-Star Wars KOTOR if you get what I am saying.

"Mass Effect was most like Kotor. How you get to choose where your ship takes you. Mass Effect is basically a non-Star Wars KOTOR if you get what I am saying.
"

Hopefully the ME engine was a test run for KoTOR 3.

It was a lot like KOTOR

I've gotten slammed for this before but I think it was a lot like Oblivion, at least in regards to structure.  There's a basic story line with multiple side quests that are tied together into their own little stories.  I thought ME was much better for a number of reasons, but still I feel they share similarities.  

Well, I don't know about anyone else, but after I finished the story it made me feel like winner.

So.. Big Rigs?

said: lol

"Hopefully the ME engine was a test run for KoTOR 3."

I was reading a lot of Mass Effect back story, and then taking into consideration all of the character arcs and such you can learn after developing your companions enough, the Mass Effect universe is a really big and interesting one, much like Star Wars (of course Star Wars is way bigger, Expanded Universe hmm?). Anyway back on topic, this game reminded me a lot of Kotor lol.